Lubricating oil



Patented Oct. 15, 1 946 2.409.303 LUBRICATING OIL John R. Morris, Lawrenceviile,

Ill, and Rush F.

McCieary, Beacon, N. Y., assignors to The Texas Company, New York, N. Y., a corporation of ware Io Drawing. Original a Serial N 390,540, dated April 24, 1945.

tion May 12, 1944, Se

This invention relates to an improved lubricating oil adapted for use in internal combustion engines and particularly to a lubricating oil having one or more additives incorporated there- This application is a division of the application of John R. Morris and Rush F. McCleary, Serial No. 390,540, filed April 26, 1941, now Patent No. 2,374,559, dated- April 24, 1945, for Lubricating oil.

It is generally conceded that in the recent development of internal combustion engines, and particularly engines designed for heavy-duty service, the increase in operating temperatures, together with the reduction of clearances and the use of hard bearing alloys, such as copper-lead, cadmium-silver, etc., have set up such severe operating conditions as to necessitate an improvement in the highly solvent-refined mineral oils refined for use as crankcase lubricants. These rigorous operating conditions, which are most prevalent in Diesel and gasoline engines used in heavy duty bus and tractor service, have seriously accentuated such problem as corrosion, oxidation and resin formation in the solvent-refined mineral lubricating oils with the resultant dele-,

terious effect on the emciency of the engines. The nature and extent or these problems depend upon the conditions of operation of the particular engine type, the type and extent of refining ofthe base oil used, and numerous other factors.

The tendency of mineral lubricating oils to deposit gums, resins, soot and varnish-like materials about the valves, rings, pistons, cylinders and other engine parts can be largely overcome by the addition of certain types of additive ingredients which possess detergent properties when dissolved or dispersed in mineral lubricating oils. By detergent properties is meant not only that property which aids in dispersing, removing or purging foreign materials which accumulate on the surface of the engine parts, but also that property which prevents the accumula-' tion or deposition of such materials, as distinguished from solvent action upon thes accumulations or deposits.

In addition thereto the added tendency of these oils to corrode the metal surfaces with which the lubricating oil comes in contact may be overcome or reduced by the addition of additive components which possess anti-oxidant or anti-corpplication April 26, 1941, now Patent N Divided and this applicarial No. 535,362

6 Claims. (01. 252-42.7)

rcsive properties when dissolved or dispersed in mineral lubricating oils. These anti-oxidant or anti-corrosive properties are meant to include all such properties which effect a reduction or bricating oil.

It is the object 01' the present invention to provide a mineral oil composition which possesses the above-mentioned detergent and anti-oxidant or anti -corrosive properties by incorporating in a mineral lubrlcatng oil a novel additive ingredient of multi-functional activity.

A further object of this invention is to provide a mineral oil composition possessing detergent properties and enhanced anti-oxidant or anticorrosive properties by combining with the abovementioned multi-functional additive an auxiliary additive ingredient and incorporating the combination in a mineral lubricating oil.

The invention is based upon the discovery of a novel class of multi-functional additives which may be broadly described as oil-soluble or oilmiscible metal derivatives of alkyl-substituted aryloxy or arylthiooxy sulfides. It has been found that when small proportions of a compound within the scope of the above general class are blended with a mineral lubricating oil, a mineral oil composition is formed possessing eiscellent detergent and anti-oxidant or anti-corrosive properties.

Specifically, the compounds of the present invention may be described as oil-soluble or oilmiscible metal salts of the class of compounds having the structure:

in which R and R represent alkyl, aralkyl, cycloalkyl or naphthenyl or naphthenyl radicals, the alkyl portion of which contains at least 5 carbon atoms. R is preferably the same as R, but may also be a different radical within the above group. X and X represent either an oxygen or sulfur atom, and n, y, z are integers of 1' or more. 11 and y are usually 1, 2, 3 or 4, while zis usually 1, 2. or 3. Either or both of the aromatic nuclei diagrammatically shown may be substituted by a by Sn may be any one Di(tridecylphenol) naphthyl, anthracyl or other condensed aromatic nuclei. The positions of the substltuent in the formula are purely diagrammatic and may be connected to any position in the aromatic nuclei. The sulfide bond between the nuclei represented of the following structural groups:

The metallic derivatives of this class of compounds, in which the hydrogen of the hydroxyl (OH) or sulfhydryl group (SH) illustrated above as XH and XH respectively, isreplaced by a metal, include any of the following metals or combinations thereof: sodium, potassium, calcium, barium, strontium, magnesium, tin, iron, cobalt, nickel, copper, manganese and chromium. These derivatives also include the partial derivatives wherein the hydroxyl or sulfhydryl groups are only partially converted into their metallic salts as follows:

R e R I Q 15 XM XH and 8,. (Where M is a divalent metal) As illustrative of the specific compounds whose oil-soluble metallic derivatives fall within the scope of the present invention, the following list of compounds is presented:

Di(pentadecy1phenol) disulfide Di(octylphenol) disulfide Di(tridecylphenol) sulfide polysulflde Di(octadecylphenol) trisulfide Di(diamylphenol) disulfide Di(dioctylphenol) sulfide Octylphenol-amyiphenol sulfide Cetylnaphthol-isoamylphenol trisulfide Di(o-phenylphenol) sulfide Di(p-phenylphenol) di'sulfide Di(p-phenylphenol) polysulfide Di(o-benzylphenol) sulfide Di(p-benzylphenol) disulfide Di(amylresorcinol) sulfide Di(octylpyrogallol) sulfide Dl(o-cyclohexylphenol) disulfide Di(p-cyclohexylphenol) polysulfide Di(o-cyclohexylphenol) sulfide Di(naphthenylphenol) sulfide Di(naphthenylphenol) disulfide Di(pentadecyl-thiophenol) sulfide Di(tridecyl-thiophenol) disulfide Di(octyl-thiophenol) polysulfide Di(o-cyclohexyl-thiophenol) disulfide Di(p-benzyl-theiophenol) disulfide Di(o-phenyl-thiophenol) disulfide Di(naphthenyl-thiophenol) disulfide The following examples illustrate suitable methods for preparing the above-described multifunctional additives:

(Where M is a monovalent metal) aluminum, Y

Example I Example [I Percent Ash 18.8 Sulfur 6.9 Free sulfur 0.86

Eample 111 To '100 grams of polymer phenol (hydroxyl No. 166) prepared by the alkylation of phenol with a mixture of olefins (Bromine No. 129), with a boiling range of 350-450 E, which was separated from the raw polymer fraction from the catalytic polymerization of gasoline, was added an equal volume of carbon disulfide. A solution of 135 grams of sulfur monochloride in an equal volume of carbon disulfide was added portionwise to the solution of polymer phenol at room temperature while stirring. The resulting solution was maintained at room temperature until'the spontaneous evolution of hydrogen chloride gas had ceased then warmed gently on a steam bath to evaporate off th solvent, unreacted sulfur monochloride, and residual hydrogen chloride. The resulting di(polymer phenol) disulfide appeared as a dark residue and gave the following analysis:

Percent Total sulfur 8.13 Free sulfur Trace Example IV In the preparation of a partially converted varium salt of di(polymer phenol) disulfide, 100 grams of di(polymer phenol) disulfide (approximately 0.135 11101), from Example 111, were reacted with 11.5 grams of anhydrous barium hydroxide (approximately 0.0675 mol) in the presence of 200 cc. of toluene. The reaction mixture was stirred and heated to reflux under an automatic water separator for four hours, thereafter filterin through cloth and filter-cel. The filtrate then was freed of solvent by heating to -90 C. in vacuo. In the resulting salt it was found that only one-half of the phenolic groups was converted to the barium salt. It analyzed 7.62% sulfur and 7.0% barium.

These compounds have been excellent detergent However, the proportions preferred herein are between 0.25 and 2.0% by weight.

the folr An additional feature of is the combi colored compound as against the usual darkcolored sulfurized compounds.

As illustrative of the anti-corrosive properties of a lubricating oil containing either or both of suits oi the following empincal tests are presented: A copper-lead bearing specimen, incased in a special non-wear bushing and rotatably unless otherwise noted, are the normal salts, e. 3., containing no free hydroxyl groups. The results of two runs at 250 F. and 350? respectively. are presented:

Bearing corrosiom-c'opper lead (10 hours) Loss of weight in mgs. Oil tested 250 F. 350 F. Reference oil 38, 39 133, Reference oil-+05% barium di (tridccyl phenolete) disulfide l, 1 67, 71 Reference oil-l-0.6% barium di (polymer-phenolate) disulilde 0,0 Reference oil+0.5% calcium di (tridecyl phenolate) disulflde 2, 3 Reference oil+0.6% barium di (polymer-phenolate) disulflde+l.0% sulfurized terpinoleua. 0, l 0. 5 Reference o1l+0.5% barium di (polymer-phenolate) disulilde+3.0% sulfurized clay tower polymers 0, 0 0.1

pended claims.

We claim: 1. A lubricating composition comprising a mineral lubricating oil having incorporated therein 0.1-5.0% by rivative of a compound of the formula in which R and R are radicals selected from the alkyl, aralkyl, cycloalky1 and other condensed of a sulfurized terpene hydrocarbon.

2. A lubricating composition comprising a min- 011 having incorporated therein 0.1 to 5.0% by weight of an oil-soluble metal salt of an alkyl substituted aryloxy sulfide and 0.5 to 5.0% by weight of a sulfurized terpene hydrocarbon.

3. A lubricating composition comprising a mineral lubricating oil having incorporated therein 0.1-5.0% by weight of an oil-soluble metal salt 7 0.1-5.0% by weight of an oil-soluble metal deriva- 5. A lubricating composition comprising a mintive of a compound of the formula: eral lubricating oil having incorporated therein 0.1 to 5.0% by weight of an oil-soluble alkaline earth metal salt of an alkyl phenol sulfide, and a 0.6 to 5.0% by weight of a sullurized terpene hydrocarbon. 6. A lubricating composition comprising a minin which R and R are radicals selected from eral lubricating oil having incorporated therein the group consisting of alkyl; aralkyl, cycloalkyl 0.1 to 5.0% by weight or an oil-soluble metal salt and naphthenyl, the ailryl portion 0! which con- 10 of an alkyl phenol sulfide and 0.5 to 5.0% by talns at least 5 carbon atoms, X and X are eleweight of a suliurized terpinolene. v ments from the group consisting of oxygen and sulfur, 1!, v, z are integers 01 at least 1, and 0.5 JOHN R. MORRIS.

to 5.0% by weight of sulfurized terpinolene. RUSH F. MccLEARY 

